Wearable computing device authentication using bone conduction

Abstract

A wearable computing device is authenticated using bone conduction. When a user wears the device, a bone conduction speaker and a bone conduction microphone on the device contact the user's head at positions proximate the user's skull. A calibration process is performed by transmitting a signal from the speaker through the skull and receiving a calibration signal at the microphone. An authentication process is subsequently performed by transmitting another signal from the speaker through the skull and an authentication signal is received at the microphone. In the event that frequency response characteristics of the authentication signal match the frequency response characteristics of the calibration signal, the user is authenticated and the device is enabled for user interaction without requiring the user to input any additional data.

The invention claimed is: 
     
       1. A computing device configured to be worn by a user, the computing device comprising:
 a transmitter-transducer configured to contact the user at a first location on the user; 
 a receiver-transducer configured to contact the user at a second location on the user; and 
 a processor operatively coupled to the transmitter-transducer and the receiver-transducer, the processor being configured to: 
 transmit a first signal via the transmitter-transducer for reception by the receiver-transducer, thereby transmitting sound between the first location and the second location on the user, the transmission altering characteristics of the first signal to produce a second signal; 
 obtain one or more calibration signals from the second signal; and 
 store calibration signal characteristics of the obtained one or more calibration signals in memory. 
 
     
     
       2. The computing device of  claim 1 , wherein the processor is further configured to authenticate the user to the computing device in the event that characteristics of a new second signal received by the receiver-transducer match the stored calibration signal characteristics. 
     
     
       3. The computing device of  claim 2 , wherein the characteristics of the new second signal match the characteristics of the stored calibration signal characteristics when the characteristics of the second signal are determined to be within a predetermined margin of error relative to the stored calibration signal characteristics. 
     
     
       4. The computing device of  claim 2 , wherein, upon authentication, the processor is configured to enable the computing device for operation by the user. 
     
     
       5. The computing device of  claim 2 , wherein, in the event that characteristics of the new second signal do not match the characteristics of the stored calibration signal, the processor is configured to disable the computing device such that the user cannot operate the computing device. 
     
     
       6. The computing device of  claim 1 , wherein, when the user is not authenticated, the processor is configured to present information to the user regarding the lack of match, and to request re-authentication of the user. 
     
     
       7. The computing device of  claim 1 , wherein the calibration signal characteristics include one or both of frequency response characteristics and impulse response characteristics. 
     
     
       8. The computing device of  claim 1 , wherein the processor is configured to cause the transmitter-transducer to emit the first signal periodically during a computing session such that the second signal is periodically produced in response to the first signal. 
     
     
       9. A computer-implemented method comprising:
 transmitting, by a processor via a transmitter-transducer of a computing device worn by a user, a first sound signal through a first location on the user; 
 receiving a second sound signal at a receiver-transducer of the computing device positioned at a second location on the user, the second sound signal being an altered version of the first sound signal caused by transmission of sound between the first location and the second location; 
 obtaining one or more calibration signals from the second signal; and 
 storing calibration signal characteristics of the obtained one or more calibration signals in memory. 
 
     
     
       10. The computer-implemented method of  claim 9 , further comprising authenticating the user to the computing device in the event that characteristics of a new second sound signal received by the receiver-transducer match the stored calibration signal characteristics. 
     
     
       11. The computer-implemented method of  claim 10 , wherein the characteristics of the new second sound signal match the characteristics of the stored calibration signal characteristics when the characteristics of the second sound signal are determined to be within a predetermined margin of error relative to the stored calibration signal characteristics. 
     
     
       12. The computer-implemented method of  claim 10 , wherein upon authentication, the method further comprises enabling the computing device for operation by the user. 
     
     
       13. The computer-implemented method of  claim 10 , wherein, in the event that characteristics of the new second sound signal do not match the characteristics of the stored calibration signal, the method further comprises disabling, by the processor, the computing device such that the user cannot operate the computing device. 
     
     
       14. The computer-implemented method of  claim 9 , wherein, when the user is not authenticated, the method further comprises presenting information to the user regarding the lack of match and requesting re-authentication of the user. 
     
     
       15. The computer-implemented method of  claim 9 , wherein the calibration signal characteristics include one or both of frequency response characteristics and impulse response characteristics. 
     
     
       16. The computer-implemented method of  claim 9 , wherein the transmitter-transducer emits the first sound signal periodically during a computing session such that the second sound signal is periodically produced in response to the first sound signal. 
     
     
       17. A non-transitory computer-readable storage medium storing instructions thereon, the instructions, when executed by a processor, cause the processor to implement a method comprising:
 transmitting a first sound signal through a first location on a user; 
 receiving a second sound signal at a second location on the user, the second sound signal being an altered version of the first sound signal caused by transmission of sound between the first location and the second location; 
 obtaining one or more calibration signals from the second signal; and 
 storing calibration signal characteristics of the obtained one or more calibration signals in memory. 
 
     
     
       18. The non-transitory computer-readable storage medium of  claim 17 , wherein the method further comprises authenticating the user to a computing device in the event that characteristics of a new second sound signal received at the second location match the stored calibration signal characteristics. 
     
     
       19. The non-transitory computer-readable storage medium of  claim 18 , wherein the characteristics of the new second sound signal match the characteristics of the stored calibration signal characteristics when the characteristics of the second sound signal are determined to be within a predetermined margin of error relative to the stored calibration signal characteristics. 
     
     
       20. The non-transitory computer-readable storage medium of  claim 18 , wherein, in the event that characteristics of the new second sound signal do not match the characteristics of the stored calibration signal, the method further comprises disabling the computing device such that the user cannot operate the computing device.